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slopes, a new seed mix for the vegetated channel, check dams and riprap <br />for the lower, steep portion of the diversion. <br />The prior coal operator, Dorchester Coal, had diverted Magpie Creek to its <br />present channel in order to keep fresh water from entering the facility <br />area. Magpie Creek was diverted by Dorchester Coal around the facility <br />area to where it is today. EFCI, as the successor operator, has been <br />granted the right to leave Magpie Creek as is, with creek stabilization <br />constructed in three phases: the first phase was initiated in 1994 and <br />second and third phase were completed with final reclamation of the site <br />in late 2001 and early 2002. <br />3. Channel lining structures, in the form of riprap, for artificial channel <br />roughness, are proposed for use to control erosion in portions of Magpie <br />Creek. The Division has approved the riprap because it is necessary to <br />control erosion, is stable and it will require infrequent maintenance. <br />(4.05.4(2)(a)). <br />For Magpie Creek diversion specifications, refer to Exhibit 19, "Drainage <br />and Sediment Control, of the permit application. <br />4. The permanent diversion of Magpie Creek shall make use of artificial <br />structural controls with the use of check dams and vegetation in order to <br />allow it to remain in dynamic equilibrium with the drainage basin system. <br />The Division proposes to approve the use of such structures. <br />(4.05.04(4)(b)). <br />C. Sediment Ponds <br />As described in Section III. A. above, there are a total of two sediment ponds at <br />the mine site and two at the loadout. Ponds 4 and 5 are used to settle sediment <br />at the mine site, while ponds L-1 and L-2 are used to settle sediment at the <br />loadout. Ponds 2 and 3 were part of a closed-loop recyclable system for water <br />storage and use in the coal processing plant. Pond 3 was a fresh water storage <br />pond, receiving water pumped from the Corley Mine well, while Pond 2 was <br />primarily used as a water treatment and recyclable water source for the coal <br />processing plant. Pond 1 was a sediment pond for drainage off of the coal <br />stockpiles. Ponds 1, 2 and 3 have been reclaimed. <br />All sedimentation ponds have been designed utilizing standard engineering <br />practices to retain the run-off from a 10-year 24-hour storm event. Pond design <br />criteria can be found in Exhibit 19 of the permit application. <br />From the 1993 Mid-term Review, stipulation 22 was added to the permit to <br />update the pond as-built certifications. The stipulation was complied with and <br />subsequently terminated. <br />Page 20 of 36